[varLib] Fix interpolate_layout for non-similar SinglePos

Has to be ported to varfont merger as well.

Lib/fontTools/ttLib/tables/otBase.py

@@ -868,6 +868,12 @@ class ValueRecord(object):
 
 	# see ValueRecordFactory
 
+	def __init__(self, valueFormat=None):
+		if valueFormat is not None:
+			for mask, name, isDevice, signed in valueRecordFormat:
+				if valueFormat & mask:
+					setattr(self, name, None if isDevice else 0)
+
 	def getFormat(self):
 		format = 0
 		for name in self.__dict__.keys():

Lib/fontTools/varLib/__init__.py

@@ -248,7 +248,8 @@ def buildVarDevTable(store_builder, master_values):
 
 class VariationMerger(Merger):
 
-	def __init__(self, model, axisTags):
+	def __init__(self, model, axisTags, font):
+		Merger.__init__(self, font)
 		self.model = model
 		self.store_builder = builder.OnlineVarStoreBuilder(axisTags)
 		self.store_builder.setModel(model)
@@ -302,7 +303,7 @@ def merge(merger, self, lst):
 
 		if hasattr(self, name):
 			deviceTable = buildVarDevTable(merger.store_builder,
-						       [getattr(a, name) for a in lst])
+						       [getattr(a, name, 0) for a in lst])
 			if deviceTable:
 				setattr(self, tableName, deviceTable)
 
@@ -310,7 +311,7 @@ def merge(merger, self, lst):
 def _merge_OTL(font, model, master_fonts, axisTags, base_idx):
 
 	print("Merging OpenType Layout tables")
-	merger = VariationMerger(model, axisTags)
+	merger = VariationMerger(model, axisTags, font)
 
 	merge_tables(font, merger, master_fonts, axisTags, base_idx, ['GPOS'])
 	store = merger.store_builder.finish()

Lib/fontTools/varLib/interpolate_layout.py

@@ -9,11 +9,13 @@ from fontTools.ttLib.tables import otBase as otBase
 from fontTools.ttLib.tables.DefaultTable import DefaultTable
 from fontTools.varLib import designspace, models, builder
 from fontTools.varLib.merger import merge_tables, Merger
+from functools import reduce
 import os.path
 
 class InstancerMerger(Merger):
 
-	def __init__(self, model, location):
+	def __init__(self, font, model, location):
+		Merger.__init__(self, font)
 		self.model = model
 		self.location = location
 
@@ -30,6 +32,7 @@ def merge(merger, self, lst):
 def merge(merger, self, lst):
 	model = merger.model
 	location = merger.location
+	# TODO Handle differing valueformats
 	for name, tableName in [('XAdvance','XAdvDevice'),
 				('YAdvance','YAdvDevice'),
 				('XPlacement','XPlaDevice'),
@@ -38,10 +41,115 @@ def merge(merger, self, lst):
 		assert not hasattr(self, tableName)
 
 		if hasattr(self, name):
-			values = [getattr(a, name) for a in lst]
+			values = [getattr(a, name, 0) for a in lst]
 			value = round(model.interpolateFromMasters(location, values))
 			setattr(self, name, value)
 
+def _SinglePosUpgradeToFormat2(self):
+	if self.Format == 2: return self
+
+	ret = ot.SinglePos()
+	ret.Format = 2
+	ret.Coverage = self.Coverage
+	ret.ValueFormat = self.ValueFormat
+	ret.Value = [self.Value for g in ret.Coverage.glyphs]
+	ret.ValueCount = len(ret.Value)
+
+	return ret
+
+def _merge_GlyphOrders(font, lst, values_lst=None):
+	"""Takes font and list of glyph lists (must be sorted by glyph id), and returns
+	two things:
+	- Combined glyph list,
+	- If values_lst is None, return input glyph lists, but padded with None when a glyph
+	  was missing in a list.  Otherwise, return values_lst list-of-list, padded with None
+	  to match combined glyph lists.
+	"""
+	dict_sets = [{g:i for i,g in enumerate(l)} for l in lst]
+	combined = set()
+	combined.update(*dict_sets)
+	order = font.getGlyphOrder()
+	order = [glyph for glyph in order if glyph in combined]
+	paddedValues = None
+	if values_lst is None:
+		padded = [[glyph if glyph in dict_set else None
+			   for glyph in combined]
+			  for dict_set in dict_sets]
+	else:
+		assert len(lst) == len(values_lst)
+		padded = [[values[dict_set[glyph]] if glyph in dict_set else None
+			   for glyph in combined]
+			  for dict_set, values in zip(dict_sets, values_lst)]
+	return order, padded
+
+def _Lookup_SinglePos_get_effective_value(self, glyph):
+	if self is None: return None
+	subtables = self.SubTable
+	for self in subtables:
+		if self is None or \
+		   type(self) != ot.SinglePos or \
+		   self.Coverage is None or \
+		   glyph not in self.Coverage.glyphs:
+			continue
+		if self.Format == 1:
+			return self.Value
+		elif self.Format == 2:
+			return self.Value[self.Coverage.glyphs.index(glyph)]
+		else:
+			assert 0
+	return None
+
+@InstancerMerger.merger(ot.SinglePos)
+def merge(merger, self, lst):
+	self.ValueFormat = valueFormat = reduce(int.__or__, [l.ValueFormat for l in lst])
+	assert valueFormat & ~0xF == 0, valueFormat
+
+	# If all have same coverage table and all are format 1,
+	if all(v.Format == 1 for v in lst) and all(self.Coverage.glyphs == v.Coverage.glyphs for v in lst):
+		self.Value = otBase.ValueRecord(valueFormat)
+		merger.mergeThings(self.Value, [v.Value for v in lst])
+		return
+
+	# Upgrade everything to Format=2
+	self.Format = 2
+	lst = [_SinglePosUpgradeToFormat2(v) for v in lst]
+
+	# Align them
+	glyphs, padded = _merge_GlyphOrders(merger.font,
+					    [v.Coverage.glyphs for v in lst],
+					    [v.Value for v in lst])
+
+	self.Coverage.glyphs = glyphs
+	self.Value = [otBase.ValueRecord(valueFormat) for g in glyphs]
+	self.ValueCount = len(self.Value)
+
+	for glyph,values in zip(glyphs, padded):
+		for i in range(len(values)):
+			if values[i] is not None: continue
+			# Fill in value from k
+			v = _Lookup_SinglePos_get_effective_value(merger.lookups[i], glyph)
+			if v is None:
+				v = otBase.ValueRecord(valueFormat)
+			values[i] = v
+
+	merger.mergeThings(self.Value, padded)
+	# Merge everything else; though, there shouldn't be anything else. :)
+	merger.mergeObjects(self, lst,
+			    exclude=('Format', 'Coverage', 'ValueRecord', 'Value', 'ValueCount'))
+
+#@InstancerMerger.merger(ot.PairPos)
+#def merge(merger, self, lst):
+#	#return #XXX
+#	# Merge everything else; though, there shouldn't be anything else. :)
+#	merger.mergeObjects(self, lst,
+#			    exclude=('Coverage', 'PairSet', 'PairSetCount'))
+
+@InstancerMerger.merger(ot.Lookup)
+def merge(merger, self, lst):
+	merger.lookups = lst
+	merger.mergeObjects(self, lst)
+	del merger.lookups
+
 
 def interpolate_layout(designspace_filename, loc, finder):
 
@@ -96,7 +204,7 @@ def interpolate_layout(designspace_filename, loc, finder):
 	model = models.VariationModel(master_locs)
 	assert 0 == model.mapping[base_idx]
 
-	merger = InstancerMerger(model, loc)
+	merger = InstancerMerger(font, model, loc)
 
 	print("Building variations tables")
 	merge_tables(font, merger, master_fonts, axes, base_idx, ['GPOS'])

Lib/fontTools/varLib/merger.py

@@ -10,6 +10,9 @@ class Merger(object):
 
 	mergers = None
 
+	def __init__(self, font=None):
+		self.font = font
+
 	@classmethod
 	def merger(celf, clazzes, attrs=(None,)):
 		assert celf != Merger, 'Subclass Merger instead.'
@@ -33,13 +36,15 @@ class Merger(object):
 			return None
 		return wrapper
 
-	def mergeObjects(self, out, lst, _default={}):
-		keys = vars(out).keys()
-		assert all(vars(table).keys() == keys for table in lst)
+	def mergeObjects(self, out, lst, exclude=(), _default={}):
+		keys = sorted(vars(out).keys())
+		assert all(keys == sorted(vars(v).keys()) for v in lst), \
+			(keys, [sorted(vars(v).keys()) for v in lst])
 		mergers = self.mergers.get(type(out), _default)
 		defaultMerger = mergers.get('*', self.__class__.mergeThings)
 		try:
 			for key in keys:
+				if key in exclude: continue
 				value = getattr(out, key)
 				values = [getattr(table, key) for table in lst]
 				mergerFunc = mergers.get(key, defaultMerger)